Cittern

n. old musical instrument with strings stretched over a flat sounding box (related to the guitar)

The cittern is a stringed instrument of the lute family dating from the Renaissance. With its flat back, it was much simpler, and therefore cheaper, to construct than the lute, in addition to which it was easier to play and keep in tune and, being smaller and less delicate, far more portable. Thus, although it was played by all classes, the cittern was a premier instrument of casual music making for the common people, much like the guitar at the present day.
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Noun
1. a 16th century musical instrument resembling a guitar with a pear-shaped soundbox and wire strings
(synonym) cithern, cither, citole, gittern
(hypernym) guitar

n. cittern

(n.)
An instrument shaped like a lute, but strung with wire and played with a quill or plectrum.